Mechanic&#39;s square



July 30, 1946. E. l. KING MEcHANIos SQUARE Filed Jan. 11, 1945 IlllxllllllllllllllLlllllllrhhhltllhll INVENTOR Elm er l. King Patented July30, 1946 UNITED STATES PATENT OFFICE MECHANICS SQUARE Elmer I. King,Jeannette, Pa. Application January 11, 1945, Serial No. 572,293

7 Claims.

'I'his invention relates to tools of the type used by artisans andmechanics and generally known as a universal square.

The conventional universal square comprises a metal straight edge orrule with a groove along one face thereof. There is a slide movablealong the rule with right angle and 45 angle faces thereon. This slideis adjustably locked in place in any position to which it may beadjusted along the rule by turning a nut which puts tension on a lockingpin, the locking pin having a lug or nib which rides in the groove ofthe straight edge. When the lug is thus put under tension, it binds inthe groove, holding the slide from moving. Sometimes it is desirable toremove the slide entirely from the rule, and if this happens, thelocking pin may rotate, moving the lug to a position where it interfereswith putting the slide back on the rule.

According to the present invention, a locking device is provided whichis much more simple and convenient to operate, simple to manufacture,and the lug on the locking pin may not, under normal conditions,obstruct the application of the slide to the rule, enabling the slide tobe removed and applied with no difficulty.

My invention may be more fully understood by reference to theaccompanying drawing in which:

Figure 1 is a side elevation of a tool embodying my invention, partsbeing broken away to better illustrate it;

Figure 2 is a transverse section in the plane of line II-II of Figure 1;

Figure 3 is an exploded view of the several parts comprising the novellocking mechanism;

Figure 4 is a fragmentary view, similar to Figure 1 showing a slightmodification; and

Figure 5 is a fragmentary sectional view of the upper part of thelocking pin assembly, showing still another modication.

Referring first to Figures 1 to 3 inclusive, 2 designates the usualmetal rule or straight-edge employed in devices of this kind and 3 is anarrow groove extending along the middle of one edge thereof.

The slide may be made as an integral casting with a base portion. 4,perpendicular arm 5 having a machined face 6 at right angles to thestraight-edgel It also has an arm 1 with a machined faceB at a 45 angleto the straightedge. A brace or frame 9 connects the outer ends of thetwo arms and there is a bubble-level at I9 on the arm 5.

Formed on the base 4 and extending between 2 the two arms 5 and 1 is aboss or projection II with a central bore therethrough. the outer O Iupper end of this bore being internally threaded. The base 4 is slottedlongitudinally on a mid plane to receive and straddle the rule orstraight,- edge 2. The base l is also formed with a borse orcounter-sunk opening I2 which forms an enlarged continuation orextension of the hole in the boss II, and this counter-bore isinternally threaded. Y

Screwed into the counter-bore I I is a threaded plug i3 that isbifurcated from its ared lower end inwardly toward the other end, theslot I4 therein being of a width to receive and snugly straddle the rule21 and when the plug I3 is screwed in to its fullest limit this slot I4is in register with the slit along the base, and its flared lower end isflush with the bottom of base 4.

A pin I5 is slidably received in the plug I 3 and extends up through theboss II. The lower end of the pin I5 has a thin extension I6 thereonwith an overhanging lug I'I at its terminal, the lug being entered ingroove 3 of the rule and the thin extension I5 iitting against one faceof the rule.

Surrounding the pin I5 inside the boss Il .is a relatively stiff coilspring i8, the lower end of this spring resting on the end of the plugI3, which provides an abutment for the spring.

At the top of the post or extension lI is a head or cap element I9having a downwardly extending tubular extension 20 that is screwed intothe top of the post. The top portion rof the cap is bifurcated,providing two ears 2l and the top of the pin I 5 projects through thecap and terminates in the space between these two ears. A transverse pin22 passing through pin 2| forms an abutment for the upper end of springI8, so that the spring I8 tends to force the pin upwardly as viewed inFigures 1 and 2. while the inner end of the tubulation on the cap limitssuch outward movement, and the tubulation may have a transverse grooveor notch 20a, at its lower end into which this pin may be projected tohold the main pin I5 from rotation.

Received between the ears, and retained in place by a pivot pin 24 is anoperating member 23 having a flat surface isa bearing against the top ofpin I5, an operating extension 23h. and a lug 23e that limits thearcuate movement of the lever in a clockwise direction (as viewed inFigure 1) by contacting the cap in the space between the ears 2|.

With the assembly as herein described, the

spring I8 exerts a relatively strong pressure through abutment 22 tourge pin I5 upwardly or outwardly, causing the lug I1 to bind againstthe upper edge vor the groove 3 in the rule 2, rmly locking the slideagainst free sliding movement. However, if pressure is applied to lever22h, tending to rotate it in a counter-clockwise direction (as viewed inFigure 1) thereby depressing pin I5 and releasing the lug Il frombinding engagement with the edge of the groove, permitting the slide tomove freely along the rule 2. Upon release of the pressure on lever 23h,spring I8 acts to push the pin I5 up and again lock the slide.

If the slide is removed from the rule, cross pin 22 is forced up intonotch 25a to hold pin I5 from turning so that when the slide is next putback on the rule, the lug will be in proper position.

The plug I3 is used to facilitate the assembly of the parts as withoutsuch a plug, machining and assembly would be more difficult.

After long usage some slight wear may take place between the outer endof the pin and the surface 23a of the operating member. rThis can becompensated for by either of the two arrangements indicated in Figure 4or 5.

In Figure 4, all of the parts are identied by reference numerals as usedin Figures 1 to 3, but ln addition there is shown a set screw 25 in theoperating member which has an innner terminal portion projecting throughsurface 23d to engage the pin, and if Wear develops this pin may beturned down. In this gure operating extension 23h is provided with abutton 23d against which the thumb or nger may be pressed.

In Figure 5 the top of the pin I5 is provided with a set screw |59: thehead of which bears against the operating member, and if wear develops,operating member 23 is removed, screw I 5a: adjusted, and the operatingmember then replaced.

While I have shown my invention as applied to one specic form of slidehaving a right angle arm and a forty-live degree arm, implements of thiskind use various other slides with different arm arrangements, and myinvention is applicable to all of these.

I claim:

l. In a tool having a rule which is longitudinally grooved and a slidehaving a face at an angle to the rule characterized by the provision ofa locking means on the slide cooperating with the groove in the rulewherein the locking means comprises a pin in the slide movabletransversely of the longitudinal axis of the rule, the pin having aterminal portion at one end to engage in the groove, a spring exertingpressure on the pin to move its said terminal into locking engagementWith the walls of the groove, said spring and pin constituting the solelocking means for the rule, and means for moving the pin against thepressure of the spring to release the terminal of the pin from suchlocking engagement.

2. In a tool having a slide member into which a rule is set edgewisewith the slide straddling the rule, the rule having a groove along onei'ace thereof, the invention comprising means for adjustably holding theslide and rule against rela- -z' tive movement comprising a pin carriedby the slide member movable transversely of the longitudinal axis of therule, the pin having an extension on its inner end with a lug that isreceived in the groove and which is adapted to bind against the walls ofthe groove to hold the slide member movable transversely of thelongitudinal axis of the rule, a spring in the slide surrounding the pinfor yieldably urging it to a position where said lug is in lockingengagement with the groove, the tension of said spring exerting the solelocking force against said rule, and an operating lever at the outer endof the pin for moving the pin against the pressure of the spring torelease the lug from locking engagement with the groove.

3. In a tool having a slide member into which a rule is set edgewisewith the slide straddling the rule, the rule having a groove along oneface thereof, the invention comprising means for ad justably holding theslide and rule against relative movement comprising a pin carried by theslide member movable transversely of the longitudinal axis of the rule,the pin having an extersion on its inner end with a lug that is receivedin the groove and which is adapted to bind against the walls of thegroove to hold the slide against movement, a spring in the slidesurrounding the pin for yieldably urging it to a position where said lugis in locking engagement with the groove, the tension of said springexerting the sole locking force against said rule, and an operatinglever at the outer end of the pin for moving the pin against thepressure of the spring to release the lug from locking engagement withthe groove, the operating lever being pivotally carried by the slide andhaving an operating extension thereon.

4. In a tool having a slide member into which a rule is set edgewisewith the slide straddling the rule, the rule having a groove along oneface thereof, the invention comprising means for adjustably holding theslide and rule against relative movement comprising a pin carried by theslide member movable transversely oi the longitudinal axis of the rule,the pin having an extension on its inner end with a lug that is receivedin the groove and which is adapted to bind against the walls or" thegroove to hold the slide against movement, a spring in the slidesurrounding the pin for yieldably urging it to a position where said lugis in locking engagement with the groove, the tension of said springexerting the sole locking force against said rule, and an operatinglever at the outer end of the pin for moving the pin against thepressure of the spring to release the lug from locking engagement withthe groove, and adjustable means for compensating for wear between. thelever and the pin.

5. In a tool having a slide member into which a rule is set edgewisewith the slide straddling the rule, the rule having a groove along oneface thereof, the invention comprising means for adjustably holding theslide and rule against relative movement comprising a pin carried by theslide member movable transversely of the longitudinal axis of the rule,the pin having an extension on its inner end with` a lng that is reiceived in the groove and which is adapted to bind against the walls ofthe groove to hold the slide against movement, a spring in the slidesurrounding the pin for yieldably urging it to a position where said lugis in locking engagement with the groove, the tension of said springexerting the sole locking force against said rule, and an operatinglever` at the outer end of the pin for moving the pin against thepressure ci the spring to release the lug from locking engagement withthe groove, and means for holding the pin against rotation.

6. A slide for universal squares andthe like comprising a base which isslotted to set edgewise of a straight edge, a plug screwed transverselyinto the base of the slide and Which is slotted to also straddle thestraight edge, the slot in the plug and in the base of the slide beingcontinuous, a boss on the base and having a hole'therein in alignmentwith the plug, a cap member on the boss, a pin passing through the plug,boss and cap member, the pin having a reduced extension at its inner endwith a lug for engaging a groove in the straight edge, a spring aroundthe pin having one end abutting against the plug, an abutment on the pinagainst which the other end of the spring bears, said spring exertingthe sole locking force against said straight edge, and a lever on thecap bearing against the top of the pin for moving the pin axially inopposition to the spring.

'7. A slide for universal squares and the like comprising a base whichis slotted to set edge- Wise of a straight edge, a plug screwedtransversely into the base of the slide and which is slotted to alsostraddle the straight edge, the slot in the plug and in the base of theslide being continuous, a boss on the base and having a hole therein inalignment with the plug, a cap member on the boss, a pin passing throughthe plug, boss and cap member, the pin havingv a reduced extension atits inner end With a lug for engaging a groove in the straight edge, aspring around the pin having one end abutting against the plug, saidspring exerting the sole locking force against said straight edge, anabutment on the pin against which the other end of the spring bears, anda lever on the cap bearing against the top of the pin for moving the pinaxially in opposition to the spring, the abutment on the pin and the capbeing intertted to restrain the pin from rotation.

ELMER I. KING.

